ETHYLENE CHLOROHYDRIN

OSHA comments from the January 19, 1989 Final Rule on Air Contaminants Project extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.

CAS: 107-07-3; Chemical Formula: ClCH₂CH₂OH

OSHA formerly had an 8-hour TWA limit of 5 ppm, with a skin notation, for ethylene chlorohydrin. The ACGIH has a ceiling limit of 1 ppm, also with a skin notation. The proposed PEL was a ceiling of 1 ppm, with a skin notation. NIOSH (Ex. 8-47) concurred with the proposed limit, and the final rule establishes this limit and retains the skin notation. Ethylene chlorohydrin is a colorless liquid with a faint, ethereal odor.

A broad range of serious health hazards are associated with exposure to this substance; these include central nervous system effects, cardiovascular effects, liver damage, kidney damage, gastrointestinal effects, skin irritation, eye irritation, and mutagenic effects. OSHA considers that all of these effects constitute material health impairments. The oral LD(50) for rats is 72 mg/kg, and the intraperitoneal LD(50) in the same species is 56 mg/kg (Goldblatt and Chiesman 1944/Ex. 1-980). In guinea pigs, the intraperitoneal LD(50) is 98 mg/kg, and the percutaneous LD(50) is 205 mg/kg (Wahlberg and Boman 1978/Ex. 1-938).

The skin absorption rate for ethylene chlorohydrin is high; Semenova and associates (1978/Ex. 1-932) determined that the LD(50) must be reduced to one-fifth of its original value if ethylene chlorohydrin is administered daily for 20 days (Semenova, Kazanina, Fedyanina et al. 1978/Ex. 1-932).

The inhalation toxicity of ethylene chlorohydrin is also high. Ambrose (1950/Ex. 1-888) reported that a single one-hour exposure at 7.5 ppm and repeated one-hour exposures at 2 ppm can be fatal to rats. Exposures of 15 minutes daily at concentrations of from 900 to 1000 ppm were fatal to rats within a few days (Goldblatt and Chiesman 1944/Ex. 1-980).

In subacute and chronic studies, rats have died from a daily dietary dose of 67.5 mg/kg (Oser, Morgareidge, Cox, and Carson 1975/Ex. 1-923). Semenova and associates (1980, as cited in ACGIH 1986/Ex. 1-3, p. 248) reported a four-month no-effect inhalation level of 0.0033 ppm; at 0.017 ppm, slight CNS changes and alterations in the urinary secretion of nitrogen were observed after four months. These investigators also observed increased chromosomal aberrations in bone marrow in rats exposed at the 0.22-ppm level for four months (Semenova, Kazanina, Fedyanina et al. 1980, as cited in ACGIH 1986/Ex. 1-3, p. 248).

Voogt and Vet (1969/Ex. 1-1205) tested ethylene chlorohydrin in Klebsiella pneumoniae and found it strongly mutagenic. This finding was confirmed by the Ames test in Salmonella typhimurium ; ethylene chlorohydrin reacts with DNA, since it inhibits the growth of DNA-deficient bacteria (Rosenkranz and Wlodkowski 1974/Ex. 1-1201). A dose-related increase of liver protein and depletion in glutathion was observed in rats after a single dose of ethylene chlorohydrin of from 10 to 50 mg/kg (Friedman, Scalera, Balazs et al. 1977/Ex. 1-1198).

One fatal and several nonfatal cases of poisoning in industrial workers have been reported from exposure (for unspecified periods of time) to ethylene chlorohydrin at levels of between 300 and 500 ppm. An autopsy of the worker who died revealed severe damage to the liver and brain, as well as effects in other organs. The survivors experienced nausea, vomiting, and irritation of the eyes, nose, and lungs (Bush, Abrams, and Brown 1949/Ex. 1-1196). Dierker and Brown (1944/Ex. 1-1197) reported that a two-hour inhalation exposure to 300 ppm was fatal in one accidental exposure. OSHA received no comments, other than that of NIOSH (Ex. 8-47), on this substance.

In the final rule, OSHA is establishing a ceiling limit of 1 ppm for ethylene chlorohydrin and is retaining the skin notation. The Agency concludes that this limit will substantially reduce the significant risk of central nervous system and other systemic effects associated with workplace exposures at the levels permitted by the TWA limit alone. The skin notation is retained because ethylene chlorohydrin is readily absorbed through the skin.